Find flights
Deals
When to book
Airlines
FAQs

Cheap flights from Seattle to Washington, D.C. Dulles Intl Airport from C$ 206

This is the cheapest one-way flight price found by a Cheapflights user in the last 72 hours by searching for a flight departing on 8/7. Fares are subject to change and may not be available on all flights or dates of travel.
SEA — IAD
8 Jul — 15 Jul1
1 adult
1 adult, Economy, 0 bags
Cheapflights Tip: The best prices from Seattle/Tacoma Intl to Washington, D.C. Dulles Intl are usually found in February or October, booked 77 days in advance, depart on a Thursday or Wednesday and return on a Monday

Cheap flight deals from Seattle to Dulles Intl

Enter your travel dates to find the best prices.

Cheapest flights from Seattle to Dulles Intl
Explore the most affordable flight options available from Seattle to Dulles Intl. Find the lowest fares from popular airlines and budget airlines, with prices last updated on 8 June 2026.

Tue 8/99:35 p.m.
SEA
-
IAD
Nonstop5h 05m
Alaska Airlines
Thu 17/97:00 a.m.
IAD
-
SEA
Nonstop5h 37m
Alaska Airlines
Deal found 4/6C$ 411
Fri 4/92:34 p.m.
SEA
-
IAD
1 stop6h 58m
United Airlines
Mon 7/96:30 a.m.
IAD
-
SEA
1 stop8h 14m
United Airlines
Deal found 5/6C$ 413
Thu 3/98:51 p.m.
SEA
-
IAD
1 stop18h 23m
Alaska Airlines
Mon 7/97:00 a.m.
IAD
-
SEA
Nonstop5h 37m
Alaska Airlines
Deal found 3/6C$ 425
Tue 29/92:45 p.m.
SEA
-
IAD
Nonstop5h 04m
Delta
Sat 3/107:10 a.m.
IAD
-
SEA
Nonstop5h 40m
Delta
Deal found 4/6C$ 426
Tue 29/98:10 a.m.
SEA
-
IAD
Nonstop5h 05m
United Airlines
Sat 3/103:35 p.m.
IAD
-
SEA
1 stop9h 21m
United Airlines
Deal found 4/6C$ 435
Wed 9/98:40 p.m.
SEA
-
IAD
1 stop18h 34m
Alaska Airlines
Mon 14/97:47 p.m.
IAD
-
SEA
1 stop16h 33m
Alaska Airlines
Deal found 7/6C$ 438
Mon 3/86:21 a.m.
SEA
-
IAD
1 stop9h 24m
Alaska Airlines
Mon 17/86:03 a.m.
IAD
-
SEA
Nonstop5h 45m
Alaska Airlines
Deal found 6/6C$ 439
Sat 26/92:45 p.m.
SEA
-
IAD
Nonstop5h 04m
Delta
Thu 1/107:10 a.m.
IAD
-
SEA
Nonstop5h 40m
Delta
Deal found 4/6C$ 440
Wed 19/811:04 p.m.
SEA
-
IAD
Nonstop5h 03m
United Airlines
Sat 29/85:33 p.m.
IAD
-
SEA
Nonstop5h 45m
United Airlines
Deal found 3/6C$ 445
Fri 10/711:20 p.m.
SEA
-
IAD
Nonstop5h 02m
United Airlines
Mon 13/75:55 p.m.
IAD
-
SEA
Nonstop5h 51m
United Airlines
Deal found 5/6C$ 452
Fri 31/710:43 p.m.
SEA
-
IAD
Nonstop4h 56m
Alaska Airlines
Mon 3/87:53 p.m.
IAD
-
SEA
1 stop16h 26m
Alaska Airlines
Deal found 4/6C$ 453
Wed 1/74:20 p.m.
SEA
-
IAD
Nonstop5h 05m
Delta
Sat 4/77:00 a.m.
IAD
-
SEA
Nonstop5h 45m
Delta
Deal found 3/6C$ 454

Find flight deals from Seattle to Dulles Intl

Discover tips and strategies to find the most affordable flight options for your journey from Seattle (SEA) to Dulles Intl (IAD). Learn about various techniques such as flexible date searches, comparing prices across and setting up price alerts. Use these methods to find the cheapest flights available for your travel needs. Data last updated 8 June 2026.

Round-trip from

C$ 411

One-way from

C$ 206

Popular in

January

Cheapest in

February

Average price

C$ 668

Good round-trip deal

C$ 1,945 or less
Alaska Airlines
  • Alaska Airlines
  • 8/9-17/9
  • Nonstop
  • 10h 42m total
  • Seattle to Washington, D.C.
Search Deals
United Airlines
  • United Airlines
  • 8/7
  • Nonstop
  • 5h 02m total
  • Seattle to Washington, D.C.
Search Deals
Highest demand for flights based on searches. 9% potential increase in price (C$ 87 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 5% potential price decrease (C$ 41 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in June 2026
Search Deals
Price to beat on a round-trip flight from Seattle/Tacoma Intl to Washington, D.C. Dulles Intl.
Search Deals

Cheapflights Fare Finder

 
Customize your flight search to find flights from Seattle to Dulles Intl that fit within your specific budget. Explore options based on user searches and filter the results based on your desired price range. Find flights that match your budget for a cost-effective journey. Over the last 7 days, Cheapflights users made 629,999 searches. Data last updated 8 June 2026.
Use the filters below to find and compare flights from Seattle to Washington, D.C. Dulles Intl Airport that are best for you.

Fly from

Fly to

Route

Depart

Return

Price

Cheapest round-trip

SeattleWashington, D.C.

SEA - IAD

SEAIAD

Seattle/Tacoma Intl

Tue 21/7

6:21 a.m.-6:45 p.m.

1 stop9h 24m

Washington, D.C. Dulles Intl

Tue 28/7

7:53 p.m.-9:19 a.m.

1 stop16h 26m

C$ 439

SeattleWashington, D.C.

SEA - IAD

SEAIAD

Seattle/Tacoma Intl

Fri 11/9

8:51 p.m.-6:14 p.m.

1 stop18h 23m

Washington, D.C. Dulles Intl

Sun 13/9

7:47 p.m.-9:20 a.m.

1 stop16h 33m

C$ 439

SeattleWashington, D.C.

SEA - IAD

SEAIAD

Seattle/Tacoma Intl

Thu 10/9

8:51 p.m.-6:14 p.m.

1 stop18h 23m

Washington, D.C. Dulles Intl

Mon 14/9

7:47 p.m.-9:20 a.m.

1 stop16h 33m

C$ 439

SeattleWashington, D.C.

SEA - IAD

SEAIAD

Seattle/Tacoma Intl

Wed 29/7

6:21 a.m.-6:45 p.m.

1 stop9h 24m

Washington, D.C. Dulles Intl

Mon 3/8

9:30 a.m.-12:16 p.m.

Nonstop5h 46m

C$ 467
Quickest round-trip

SeattleWashington, D.C.

SEA - IAD

SEAIAD

Seattle/Tacoma Intl

Fri 3/7

9:13 a.m.-5:11 p.m.

Nonstop4h 58m

Washington, D.C. Dulles Intl

Sun 5/7

6:03 a.m.-8:48 a.m.

Nonstop5h 45m

C$ 474

SeattleWashington, D.C.

SEA - IAD

SEAIAD

Seattle/Tacoma Intl

Sun 6/9

11:59 p.m.-11:28 a.m.

1 stop8h 29m

Washington, D.C. Dulles Intl

Mon 7/9

5:33 p.m.-8:18 p.m.

Nonstop5h 45m

C$ 498

SeattleWashington, D.C.

SEA - IAD

SEAIAD

Seattle/Tacoma Intl

Fri 25/9

8:51 p.m.-6:14 p.m.

1 stop18h 23m

Washington, D.C. Dulles Intl

Sun 27/9

7:47 p.m.-9:20 a.m.

1 stop16h 33m

C$ 509

SeattleWashington, D.C.

SEA - IAD

SEAIAD

Seattle/Tacoma Intl

Thu 1/10

6:51 p.m.-6:28 a.m.

1 stop8h 37m

Washington, D.C. Dulles Intl

Sun 4/10

12:55 p.m.-3:40 p.m.

Nonstop5h 45m

C$ 512

SeattleWashington, D.C.

SEA - IAD

SEAIAD

Seattle/Tacoma Intl

Fri 16/10

8:15 a.m.-4:33 p.m.

Nonstop5h 18m

Washington, D.C. Dulles Intl

Mon 19/10

7:24 p.m.-9:28 a.m.

1 stop17h 04m

C$ 512

SeattleWashington, D.C.

SEA - IAD

SEAIAD

Seattle/Tacoma Intl

Wed 9/9

6:15 p.m.-5:25 a.m.

1 stop8h 10m

Washington, D.C. Dulles Intl

Mon 14/9

5:33 p.m.-8:18 p.m.

Nonstop5h 45m

C$ 521

Flights are sorted by cheapest round-trip flights first.

Deals found on 5/6

Showing 1-10 of 23 resultsSorted by cheapest first
1
2
3

Best time to book a flight from Seattle to Dulles Intl

Have a flexible travel schedule? Discover the best time to fly to Dulles Intl from Seattle with our price prediction graph.
Estimated round-trip price
Rates are based on past data. Find the cheapest month and day to book your flight based on your travel requirements, then search for cheap deals.

Cheapflights Insights

Everything you need to know about your flight from Seattle to Washington, D.C. Dulles Intl Airport

How far ahead should I book a flight from Seattle to Washington, D.C. Dulles Intl Airport?

Booking 64 days in advance of your planned departure date is, on average, the best time to get cheap flights from Seattle to Washington, D.C. Dulles Intl Airport. The general trend is that the closer you book to the departure date, the more expensive your flight will be.

What is the cheapest month to book a flight from Seattle to Washington, D.C. Dulles Intl Airport?

Currently, February is the cheapest month in which you can book a flight from Seattle to Washington, D.C. Dulles Intl Airport (average of C$ 422). Flying from Seattle to Washington, D.C. Dulles Intl Airport in January is currently the most expensive (average of C$ 913). There are several factors that can impact the price of a flight, so comparing airlines, departure airports and flight times can provide users with more options.

What is the cheapest time of day to fly from SEA to IAD?

Find hourly flight availability from Seattle to Dulles Intl. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated 8 June 2026.

A simple way to save on the total cost of your ticket is to fly from Seattle to Washington, D.C. Dulles Intl Airport in the afternoon. If you’re flexible enough to do this you can expect to save up to 72% on your trip compared to booking a flight at noon.

How much does it cost to fly round-trip from Seattle to Washington, D.C. Dulles Intl Airport?

Reviews of airlines servicing Dulles Intl

Get insights into the airlines that provide service to Dulles Intl. Read reviews, discover amenities, and learn about the overall travel experience offered by airlines. Use this information to make informed decisions when choosing an airline for your flight to Dulles Intl. Reviews last updated 8 June 2026.
Read reviews from past customers who have flown Hawaiian Airlines from Seattle to Washington, D.C. Dulles Intl Airport. Users can see the overall rating for each airline as well as how each is rated in terms of entertainment options, comfort, food, crew/service, and boarding process.
Hawaiian Airlines
7.8
Good
2,830 reviews
Check prices

Boarding

8.0

Comfort

7.7

Overall

7.8

Food

6.9

Crew

8.5

Entertainment

7.1

Reviews

1 / 20
6.0
Good

Patrick,Feb 2026

SEA - PHX

Was not able to check in online, had to go to multiple lines at airport to get boarding pass and was not able to get a seat without going to the gate, wound up in middle in the back.
Hawaiian Airlines
7.8
Good
2,830 reviews
Hawaiian Airlines
7.8
Good
2,830 reviews
Check prices

Boarding

8.0

Comfort

7.7

Overall

7.8

Food

6.9

Crew

8.5

Entertainment

7.1

Reviews

1 / 20
6.0
Good

Patrick,Feb 2026

SEA - PHX

Was not able to check in online, had to go to multiple lines at airport to get boarding pass and was not able to get a seat without going to the gate, wound up in middle in the back.

Related info for your journey

Find useful and relevant information for your journey from Seattle to Dulles Intl. Access travel guides, tips, and recommendations to enhance your travel experience. Get information about local attractions, weather, transportation options, and more.

  • What airport do you fly from for flights from Seattle to Washington, D.C. Dulles Intl?

    If you book a flight to Washington, D.C. Dulles Intl from Seattle, you will be flying from Seattle/Tacoma Intl, which is the city’s only airport. Seattle/Tacoma Intl (SEA) is located 18.4 km from the centre of Seattle. There are 17 flights from Seattle/Tacoma Intl to Washington, D.C. Dulles Intl per day from 1 airline.

  • How long is the flight from Seattle to Washington, D.C. Dulles Intl Airport?

    Alaska Airlines can get you from Seattle to Washington, D.C. Dulles Intl Airport in just under 9h 24m. Your travel time can differ by up to . Seattle and Washington, D.C. Dulles Intl Airport are separated by a distance of 3700 km.

  • What is the cheapest airline to fly from Seattle to Washington, D.C. Dulles Intl Airport round-trip?

    Our cheapest airline available from Seattle to Washington, D.C. Dulles Intl Airport is Hawaiian Airlines. Our recent data shows that you can find tickets from as low as C$ 366 on this airline. Hawaiian Airlines is 39% cheaper than the average price of flights available within the next 90 days to this destination.

  • What are the most reliable airlines from Seattle to Washington, D.C. Dulles Intl Airport?

    Looking for the most reliable airlines to get you to your destination on time? Our data shows these are most likely to get you from Seattle to Washington, D.C. Dulles Intl Airport on time: Avianca (91%), Ethiopian Air (90%), Japan Airlines (90%).

  • What are the cheapest flights from Seattle to Washington, D.C. Dulles Intl Airport?

    While on average a flight from Seattle to Washington, D.C. Dulles Intl Airport is generally C$ 2,055, our data shows the cheapest flight currently is C$ 1,945. When looking at the most popular route, (Seattle/Tacoma Intl - Washington, D.C. Dulles Intl), you can expect to pay C$ 479 for that flight.

  • Can I find deals for flights from Seattle to Dulles Intl that include hotel bookings?

    Yes. In addition to deals on Seattle to Dulles Intl flights, Cheapflights offers vacation packages that include both flights and hotel.

  • How can I find direct flights from Seattle to Dulles Intl?

    After entering your origin and destination, apply the non-stop filter on the search result page to find direct flights from Seattle to Dulles Intl.

  • Can I find deals for business class flights from Seattle to Dulles Intl?

    Yes. Cheapflights offers flight deals from Seattle to Dulles Intl by cabin class. In addition to browsing deals, you can also filter by cabin class on the search results page after making a search.

  • What is the cheapest month to book a flight from Seattle to Washington, D.C. Dulles Intl Airport?

    Currently, February is the cheapest month in which you can book a flight from Seattle to Washington, D.C. Dulles Intl Airport (average of C$ 422). Flying from Seattle to Washington, D.C. Dulles Intl Airport in January is currently the most expensive (average of C$ 913). There are several factors that can impact the price of a flight, so comparing airlines, departure airports and flight times can provide users with more options.

See more FAQs

Travelling to a place near Washington, D.C. Dulles Intl Airport?

Book flights to Washington, D.C. Dulles Intl Airport if you plan to visit one of these locations
Silver Spring
Warrenton
Winchester
Hanover
Fairfax
Reston
Ellicott City
Oxon Hill
Gaithersburg
Arlington
Chantilly
Herndon
Fredericksburg
Alexandria
Rockville

Browse thousands of different options on Cheapflights for your next trip

Toggle through the tabs below to find thousands of options on Cheapflights for your next trip.

Alternative routes for Seattle to Dulles Intl

See prices for flight routes from nearby airports that may be better suited for you.
Seattle to Reagan-National flights

Top airline flying from Seattle to Dulles Intl

Discover the top airline that operate flights from Seattle to Dulles Intl. Compare their services, reliability, and customer satisfaction ratings to choose the airline that best suits your travel preferences and needs. Over the last 7 days, Cheapflights users made 629,999 searches. Data last updated 8 June 2026.
AirlineCheapestAverageFlexibilityOn-time
Hawaiian AirlinesCheapestC$ 366AverageC$ 366FlexibilityNo cancel feeOn-time85%
Search Hawaiian Airlines flights

Fly with Cheapflights

Find the best flight deals on Cheapflights, where travelers can enjoy low prices and a wide availability of flights to their desired destinations.

How does Cheapflights help users find flights from Seattle to Dulles Intl?

900+ travel sites are searched through when a user searches for a flight using Cheapflights. From the search interface, users can use filters to choose airlines, airports, flight times, cabin classes and more to their preference. Book your flight to Dulles Intl from Seattle today with Cheapflights!

Why should you use Cheapflights to find cheap flight tickets from Seattle to Dulles Intl?

Cheapflights helps you find that perfect flight to Dulles Intl from Seattle by searching from hundreds of airlines and agencies you know and love. We are also free to use, in case you were wondering!

Can Cheapflights find flights from Seattle to Dulles Intl with no change fees?

Cheapflights does show flights with no change fees to all users. To see these options for flights from Seattle to Dulles Intl, users can toggle the no change fees filter when performing a flight search.

Can Cheapflights notify me if prices for flights from Seattle to Dulles Intl become cheaper?

Yes, and it’s super simple to set up. Click the bell icon next to the flight deals above and provide a valid email address to enable Price Alerts. That’s it!

100% Free

Cheapflights is completely free to use, so you can start saving the moment you arrive.

Book with Flexibility

Our users can plan ahead with confidence and find flights with no change fees

Travel Smart

Millions of people come to us for their flight needs every year. We help make travel planning easy by providing useful insights and data-driven graphs that can inform your decisions.